You can think of Mailhero as a super-human shield between you and the mails sent by evil spammers.
It's really quite simple. Mailhero receives all mail coming to all addresses @mailhero.io. If the mail alias used (the first part of the address, ie. email@example.com) is active, then we forward it to your real address. If the alias has been inactivated by you, then we don't and the mail instead ends up in the great big bit-bucket in the sky.
I have been creating webapps like this for a long time and I always make sure to have really low infrastructure costs for any project. This ensures that I can keep sites running indefinitely. The most widespread site that I have been a part of launching is probably Shorl.com which has been up and running since 2001 even though it has had millions of users over the years (longer than, say, Gmail which was first launched as a closed beta in 2004).
That is a sound question. Firstly, you should not trust any email service provider 100%. I would urge you to use PGP or similar software for sensitive data, and to only use a self-hosted mail server for important accounts. But, the purpose of Mailhero is rather the opposite: to ensure that unwanted mail does not reach you. Therefore, my suggestion is that you try out Mailhero for those cases were you aren't sure of the other parties intention. That way you will get a feeling for how the service works, how well it performs and, hopefully, how trustworthy it really is.
It was created by Josef Falk who has been creating sometimes useful and sometimes weird projects on the Internet as a hobby for a couple of decades now. He is one of the authors of Shorl.com mentioned above, Vinranka.com (A Swedish site which ranks wines based on the words in their descriptions), Scropple.com (a tool that let's you find the perfect word in Scrabble, Wordfeud, Betapet etc.), Upperct.com (a dynamic youtube video ranker) and others too small or silly to mention.
You can reach Joe at firstname.lastname@example.org, if you happen to have any questions what so ever.
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